Direct synthesis and dehydrogenation properties of NaAlH4 catalyzed with ball-milled Ti-B
Direct synthesis and dehydrogenation properties of NaAlH4 catalyzed with ball-milled Ti-B
复制标题
球磨Ti-B催化NaAlH4的直接合成及脱氢性能
DOI：
10.1007/s12598-016-0772-x
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发表时间：
2017
期刊：
影响因子：
8.8
通讯作者：
Yuan Hua-Tang
中科院分区：
文献类型：
--
作者：
Li Li;Zhang Zi-Chao;Wang Yi-Jing;Jiao Li-Fang;Yuan Hua-Tang
采用机械球磨法直接合成了Ti-B掺杂氢化钠铝。在1 MPa的氢气压力下70 h后，将混合物完全氢化成NaAlH 4。较高的氢压有利于NaH/Al混合物向NaAlH 4的转化。系统研究了Ti-B掺杂钠铝合金的脱氢性能。结果表明，球磨Ti-B对提高NaAlH 4的脱氢性能具有显著的催化作用。合成的Ti-B掺杂NaAlH 4样品在约100 °C的温度下释放氢。球磨Ti-B掺杂NaAlH 4在233.7 °C下释放出约4.15wt%的H2。即使在110 °C下，它也释放约2.83重量%的氢。利用Arrhenius方程估算了第一步反应的表观活化能Ea为83.97 kJ·mol-1。因此，利用球磨Ti-B作为催化剂将大大提高NaAlH 4储氢的实际应用。
AbstractBall-milled Ti–B-doped sodium aluminum hydride was directly synthesized via mechanical ball-milling of a NaH/Al mixture. The mixture was completely hydrogenated to NaAlH4after 70 h under hydrogen pressure of 1 MPa. And higher hydrogen pressure is beneficial for the conversion from NaH/Al mixture to NaAlH4. The dehydrogenation properties of the as-synthesized Ti–B-doped sodium aluminum were systematically investigated. The result shows that ball-milled Ti–B has a remarkable catalytic effect on the enhanced dehydrogenation properties of NaAlH4. As-synthesized Ti–B-doped NaAlH4sample releases hydrogen at the temperature of about 100 °C. Approximately 4.15 wt% H2is released from ball-milled Ti–B-doped NaAlH4at 233.7 °C. Even at 110 °C, it also releases about 2.83 wt% hydrogen. The apparent activation energy (Ea) for the first step is estimated to be 83.97 kJ·mol−1using Arrhenius equation. Thus, utilization of ball-milled Ti–B as catalyst would substantially enhance the practical applications of NaAlH4for hydrogen storage.